The following background information may present examples of specific aspects of the prior art (e.g., without limitation, approaches, facts, or common wisdom) that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon.
Generally, a thermal, or vacuum flask is an insulating storage vessel that greatly lengthens the time over which its contents remain hotter or cooler than the flask's surroundings. The vacuum flask consists of two flasks, placed one within the other and joined at the neck. The gap between the two flasks is partially evacuated of air, creating a near-vacuum which significantly reduces heat transfer by conduction or convection.
In many instances the occupants of moving vehicles attempt to carry beverage containers with them and to imbibe while driving or riding. It is the practice of many individuals to carry coffee, tea, and soft drinks in containers to sip while traveling in vehicles. However, because of the sway, vibration and bouncing movement encountered in most automobiles, trucks, trains, bicycles, and other vehicles, beverages frequently spill over the rim of a conventional open mouthed cup. Moreover, the motion transmitted from the vehicle will tilt and jostle a container, causing it to be upset from an otherwise stable upright position, and to spill on its side. The beverage is thus totally lost and unavailable for consumption. Also, such spillage creates a mess which is difficult to clean and which represents a source of extreme frustration and annoyance to travelers.
Moreover, when the liquid within the container is hot, such as hot coffee, liquid spilling over the side of the cup burns the fingers of a person holding the cup. This represents a considerable hazard since the individual holding the cup wishes to hurriedly put the cup down in order to wipe the hot liquid from his fingers, but cannot do so without further inattention to driving. Moreover, the liquid in the container is likely to spill entirely if the cup is placed on the seat or floor since the individual holding the cup can no longer cushion it from road shocks and swaying movement.
It is often desirable to have two different fluidic beverages available simultaneously for selective consumption or for mixing. This is especially true in the case of present day coffee service as both ordinary coffee and decaffeinated coffee have substantial popularity and commonly are served simultaneously. This need has been considered in the past and responsively various serving containers for the selective service of two or more beverages have heretofore become known.
It is therefore desirable that containers for consuming hot or cold beverages provide some means for maintaining the temperature of a contained beverage. This need has been met primarily by providing a container of thin walled construction and with relatively high heat conductivity that is maintained in an appropriate thermal environment during storage or other non-use periods. Or by providing a container of thicker walled, thermally insulative construction that has a sufficiently low thermal conductivity so that it may be stored for periods of time in areas of different ambient temperature and yet maintain the temperature of contained beverages.
Vacuum insulated containers variously known as vacuum or thermos bottles or Dewar flasks have been in use for a substantial number of years to provide thermal insulation for various materials desired to be held at or near a particular temperature for prolonged periods of time. Such containers consist of a double-walled receptacle formed of either metal or glass with the space between the walls being evacuated so as to provide the best possible vacuum in that space. Because the vacuum or substantial vacuum in that space is a very poor conductor of heat, there is consequently a minimum of heat loss through the container walls.
Other proposals have involved thermal vessels that maintain fluids at temperatures for a duration. The problem with these containers is that they do not maintain two distinct fluids at separate temperatures. Also, the two fluids cannot be dispensed independently of each other, where if one is opened, the other remains closed. Even though the above cited containers meets some of the needs of the market, a vacuum insulated container bifurcated into two compartments that are separated by vacuum insulation for containing a first fluid of a first temperature and a second fluid of a second temperature; and further providing a cap having two independent tabs that selectively open and close independently of each other, so that only one tab can be opened at one time to access the desired fluid is still desired.